A pressure sensor that uses a micro electro mechanical systems (MEMS) technology includes, for example, a piezoresistance change type and an electrostatic capacitance type. On the other hand, a pressure sensor that uses a spin-electronics technology has been proposed. In the pressure sensor using the spin-electronics technology, a resistance change corresponding to strain is sensed. For example, in a strain sensing element that is used in the pressure sensor or the like using the spin technology, it is desirable to enhance the sensitivity.